Re: Highest % of ex-NG still in service

I think the East and West Texas might be another. It became part of the Cotton belt I think.
There was a short (50-70) mile line from St. Louis to Cairo, Illinois that connected the southern and western narrow gauges and the Ohio lines. I think all of it is now part of the Cotton Belt also.
Need to check with the Narrow Gauge Bible (I don't have one here at work).
The Monroe Railroad was built to southern standard gauge (5') and then became part of the Gainesville Jefferson and Southern which converted it to 3' gauge. when the GJ&S pulled up the Monroe branch, the Walton RR took over the old Monroe RR from Monroe to Social Circle and standard gauged it (56.5"). Its 10 odd miles is 100% in operation today as a short line.
Doug vV